Adaptive Bit Rate (ABR) technology is emerging as a popular media technology to support Internet Protocol Television (IPTV) services for broadband users. In an ABR streaming system, a content item is encoded into multiple streams of different bit rates, with each stream being divided into sequential segments of a given duration (e.g. 2-10 seconds). An approach to provide broadband services to multi-dwelling unit (MDU) users is to extend a passive optical network connection to the boundary of a MDU and then distribute the broadband services over physical connections that are specific to the MDU in a broadcast nature. In this respect, IPTV services can be served on a subscriber data network that is configured in a tree topology, with the network rooted at a root node (e.g., at an optical line terminator (OLT)) and branching out to coax media converters (CMCs) via a passive optical distribution network, and further to gateway devices (GWs) that serve leaf devices such as set-top boxes and other operably-connected computing devices (e.g., personal computers and mobile devices) via a coax cable distribution network.
To provide ABR-based IPTV services, an ABR Client uses HTTP protocol to retrieve video program segments from an ABR Server. The HTTP protocol is based on IP unicasting. However, since ABR uses IP unicast, the distribution creates significant bandwidth requirements across the optical and cable distribution networks in high-user-density MDU environments. For example, if multiple users watch the same live TV programming channel at the same time, multiple copies of the same sequence of video segments need to be streamed from the wide-area-network (WAN) side to the corresponding ABR clients. This can overload the optical and cable distribution networks if too many ABR video streams are transported over them at the same time, because of the tree structures of these two networks.